Generally, a syringe is a tool used to inject a medicinal fluid into human tissue and is composed of: a tip portion to which a needle is connected; a cylinder insertedly connected to the tip portion and having a space; and a rod bar connected to the space and for injecting medicine or extracting human tissue through a needle using a positive pressure or a negative pressure generated by increasing pressure of the space by being linked with a pulling or pushing motion of the rod bar.
Here, a flange is formed to protrude at an end of the cylinder and an end of the rod bar, respectively.
When medicine is injected into the human body or human tissue is extracted through the syringe configured as above, negative pressure is generated by a motion of sticking a needle into the body, and then pulling the rod bar backward in a state of holding onto the cylinder and the rod bar using both hands, thereby extracting the human tissue, or the positive pressure is generated by a motion of pushing the rod forward, thereby injecting medicine into the body.
However, when injecting medicine or extracting human tissue using the syringe according to the conventional art, an operator's one hand is used to help enable easy injection or extraction such as rubbing an injection site and to correct an injection subject's posture, and another hand is used to move the rod bar of the syringe forward or backward.
At this time, an injecting motion of the syringe using one hand is performed by grasping the cylinder and the flange of the rod bar with the fingers and moving them forward or backward in such a state. However, it is problematic in that the injecting motion may cause a mistake of the injection procedure by increasing inconvenience.
Also, when injecting a lot of medicine into the body using a high-capacity syringe or injecting viscous medicine, in a case where a high positive pressure is generated in a space inside the syringe, it is problematic in that the tip portion insertedly connected to the cylinder is separated.
In reverse, during extracting viscous fat from the human body during a transplantation procedure of fat for correcting a shape of the body, when a high negative pressure is generated in the space inside the syringe, it is problematic in that it is difficult to perform the pulling motion of the rod bar using one hand.
Moreover, when performing a liposuction operation, fat is sucked inside the syringe space through the needle in such a manner as to put the needle into the body, and then pull out the rod bar mounted with a piston backward to generate a negative pressure inside the syringe. At this time, when a tip of the needle is exposed to the air due to the operator's mistake, the negative pressure inside the syringe is destroyed, whereupon liposuction is discontinued.
In reverse, in the procedure of injecting medicine into the body, the operator should inject the medicine by generating a positive pressure by applying constant power according to different kinds of viscosity of each medicine, but when positive pressure is excessively generated, it is problematic that tissue around an injection site of the body may be damaged.
As a result, since the generation of a stable positive or negative pressure of the syringe depends completely on the operator's judgment based on physical resistance felt from his or her hand, it is problematic in that it is difficult to accurately perform a fat extraction procedure or a medicine injection procedure.